Unusual formation of air bubbles in the arms of the California two-spot octopus, Octopus bimaculatus Verrill, 1883 during handling in captivity
Publication Type: |
Journal Article |
Year of Publication: |
2023 |
Authors: |
Graciela Esmeralda Colunga-Ramírez, Oscar B. Del Rio-Zaragoza, Sheila Castellanos-Martínez |
Publication/Journal: |
Marine Biology |
ISBN: |
1432-1793 |
Abstract:
Octopus bimaculatus from Bahia de Los Angeles, Baja California, Mexico, is a poorly known species which sustains a commercial fishery and has aquaculture potential in the Mexican Northwest. We are currently conducting research aimed at recording the pathogens and diseases that affect O. bimaculatus in the wild and captivity. In this context, six female octopuses were collected by traps in February 2022 from Bahia de Los Angeles fishery and held in captivity in flow-through system. After 26 days in captivity, air bubbles in the arms and mantle of one female were observed. This first case occurred when the female was transferred to a temporary shelter to allow routine cleaning of tanks. Air bubbles persisted for 24 h, and spawning started during this time. Air bubbles were again observed in two females after 62 days in captivity during handling to anaesthetise the octopuses for biological sampling. In this case, air bubbles disappeared while the anaesthesia was taking effect. Bacterial infection and gas bubble diseases were ruled out as potential causes; air bubbles were not associated with biochemical changes in the haemolymph of affected specimens. To our knowledge, this is the first report of air bubbles in the epidermis of a cephalopod species. Thus, air bubbles appeared in three females of O. bimaculatus during handling. This anomalous result points to the need to further investigate species-specific physiological and behavioural responses to stress caused by handling, allowing assessment of animal health and wellbeing of cephalopod species in captivity.